What you're seeing
A small bright emissive mesh produces noisy, flickering, or view-dependent indirect light.
Likely causes
- The emitting surface is too small or too intense for stable sampling.
- Lumen culls the small mesh from Lumen Scene and only screen traces retain it.
- The source changes enough luminance to make global illumination unstable.
Check in this order
- 01Inspect whether the emitting mesh appears in Lumen Scene.
- 02Increase the emitting area or reduce extreme emissive intensity while preserving the intended output.
- 03Enable Emissive Light Source on the mesh instance when the small emitter must remain represented.
- 04Check TSR Flickering Analysis only after the Lumen source is stable.
Views and commands
Lumen Scene
View Mode > Lumen > Lumen SceneShows whether the small emitting mesh is represented by Lumen.
Mesh instance setting
Lighting > Emissive Light SourceKeeps an important small emissive mesh represented in Lumen Scene.
TSR Flickering Analysis
r.TSR.Visualize 7Shows temporal flicker that remains after the Lumen source is corrected.